The present invention relates to NPN transistor amplifiers and, more particularly, to such an amplifier which is suited to be used as a video amplifier in a television IF video demodulator section.
In high quality television receivers it is required to obtain low differential gain and phase distortion in the video IF demodulator section of the television receiver to prevent undesirable distortion of the video signal. One source of the aforementioned distortion is the video amplifier of the IF demodulator section. It is therefore desirable to provide a video amplifier in the television receiver which exhibits the foregoing requirements.
Typically the input signal to the video amplifier is supplied from the output of the video demodulator Since the demodulator differential output signal is usually at or near the positive supply voltage it must be level shifted downward toward the negative supply voltage in order to obtain usable video signal levels.
Hence, a need exists for an improved differential to single ended amplifier circuit which is suitable for use as a television video amplifier having reduced differential gain and phase errors while providing accurate voltage level shifting.